Kuzmich S, Marky L A, Jones R A
Nucleic Acids Res. 1983 May 25;11(10):3393-403. doi: 10.1093/nar/11.10.3393.
Two hexamer DNA fragments containing a carcinogenic modified base, O6-methyl guanine, have been synthesized by a solid-phase phosphotriester method, in which the unmodified guanine residues present were O6 protected with the 4-nitrophenylethyl group. These two alkylated oligonucleotides were found to have similar Tm's about 40 degrees lower than the unmodified parent compound, d(CG)3. Moreover, the presence of the (O6Me)G appears to inhibit the B leads to Z transition, as determined by CD spectroscopy.
通过固相磷酸三酯法合成了两个含有致癌修饰碱基O6-甲基鸟嘌呤的六聚体DNA片段,其中存在的未修饰鸟嘌呤残基用4-硝基苯乙基进行了O6保护。发现这两个烷基化寡核苷酸的熔解温度(Tm)相似,比未修饰的母体化合物d(CG)3低约40摄氏度。此外,圆二色光谱法测定结果表明,(O6Me)G的存在似乎抑制了B型向Z型的转变。